Field of the Invention
Embodiments of the invention relate to electronic systems, and in particular, to serial interfaces for electronic communication devices and systems.
Description of the Related Technology
Radio frequency front ends (RFFE) used in conjunction with devices such as smart phones, tablets, computers and the like are increasingly required to have more control states that further require the control of additional peripheral or downstream devices. Typically, the added control states for controlling additional peripheral devices are accomplished using standard general purpose input and output (GPIO) interfaces or a standard serial MIPI RFFE type interface.
However, these interfaces can consume a significant amount of resources of an IC. For example, increasing the amount of GPIO signals requires more use of area on the master and slave dies for wire bond connections. This issue is particularly problematic with flip chip style dies. Moreover, this approach further results in greater routing size and complexity issues and can also result in corruption of the GPIO signals by the RF signals.
Similarly, using established MIPI RFFE type serial interfaces is also problematic as adding this complex interface to each of the peripherals increases die complexity and will result in redundant circuitry on different peripheral devices within the module which can increase costs. Further, the routing of MIPI RFFE interface signals to multiple devise within a module can add a signal aggressor that can cause RF performance issues which further adds to routing complexity issues.
There is a need for improved serial interfaces. Furthermore, there is a need for slave devices for serial interfaces that consume less routing resources, and which do not require additional slave addresses, register mapping tables, and/or pins.